... come on guys, they're not nearly as bad as you make them out to be. In fact, they practically eliminate the need for additional mechanical & chemical filtration by turning your substrate into one giant filter (doesn't work with sand, though).
They can keep water stunningly clear when properly taken care of, i.e.
they do require regular use of a gravel vac - easily done during regular water changes. The only reason for a UG backing up is poor maintenance.
For less gravel clean-up, get a reversible powerhead (Penguin 550R, for example), with a filter at the intake instead of the regular airstone set-up. This adds some mechanical/chemical filtration which results in far less mulm to be removed on a regular basis.
Hope I'm not stepping on any toes here
; I have been lurking around this forum for a while now and finally decided to join/post and simply couldn't resist the opportunity to defend my favourite filter system.